.Net6 to .Net8 upgrade - System.InvalidOperationException: This operation is only valid on generic types.

[JimGolden]

Attempting to upgrade our solutions from .Net 6 to .Net 8. Encountering a new exception stack trace. This is working fine from .Net 6.

I appreciate any guidance on how to troubleshoot this issue, Thank you!

Executing file 'C:\Users\jgolden.nuget\packages\bstglobal.common.hosting.aspnetcore\4.100.801.5005\build\nswag.json' with variables 'AssemblyTitle=BSTGlobal.Framework.WebApi,InformationalVersion=4.100.801.1,TargetDir=C:\TFS\BST10-Framework\Branch\Feature\dotnet8\src\BSTGlobal.Framework\BSTGlobal.Framework.WebApi\bin\Debug\net8.0,TargetName=BSTGlobal.Framework.WebApi,TargetPath=C:\TFS\BST10-Framework\Branch\Feature\dotnet8\src\BSTGlobal.Framework\BSTGlobal.Framework.WebApi\bin\Debug\net8.0\BSTGlobal.Framework.WebApi.dll,ProjectDir=C:\TFS\BST10-Framework\Branch\Feature\dotnet8\src\BSTGlobal.Framework\BSTGlobal.Framework.WebApi"'...
Launcher directory: C:\NSwag\NSwag-master\NSwag-master\artifacts\bin\NSwag.ConsoleCore\debug_net8.0
System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation.
---> System.InvalidOperationException: This operation is only valid on generic types.
at System.RuntimeType.GetGenericTypeDefinition()
at Namotion.Reflection.ContextualType.<get_Fields>b__36_0(FieldInfo field)
at System.Linq.Enumerable.SelectArrayIterator2.Fill(ReadOnlySpan1 source, Span1 destination, Func2 func)
at System.Linq.Enumerable.SelectArrayIterator2.ToArray() at Namotion.Reflection.ContextualType.get_Fields() at NJsonSchema.NewtonsoftJson.Generation.NewtonsoftJsonReflectionService.GenerateProperties(JsonSchema schema, ContextualType contextualType, NewtonsoftJsonSchemaGeneratorSettings settings, JsonSchemaGenerator schemaGenerator, JsonSchemaResolver schemaResolver) at NJsonSchema.Generation.ReflectionServiceBase1.NJsonSchema.Generation.IReflectionService.GenerateProperties(JsonSchema schema, ContextualType contextualType, JsonSchemaGeneratorSettings settings, JsonSchemaGenerator schemaGenerator, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.GenerateInheritance(ContextualType type, JsonSchema schema, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NSwag.Generation.OpenApiSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](TSchemaType schema, ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](Type type, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate(Type type, JsonSchemaResolver schemaResolver)
at NSwag.Generation.OpenApiSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](TSchemaType schema, ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate(ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.GenerateInheritance(ContextualType type, JsonSchema schema, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NSwag.Generation.OpenApiSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](TSchemaType schema, ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](Type type, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate(Type type, JsonSchemaResolver schemaResolver)
at NSwag.Generation.OpenApiSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](TSchemaType schema, ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](Type type, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate(Type type, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.AddKnownType(Type type, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.GenerateKnownTypes(Type type, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NSwag.Generation.OpenApiSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](TSchemaType schema, ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](Type type, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate(Type type, JsonSchemaResolver schemaResolver)
at NSwag.Generation.OpenApiSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](TSchemaType schema, ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate(ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.GenerateInheritance(ContextualType type, JsonSchema schema, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NSwag.Generation.OpenApiSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](TSchemaType schema, ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](Type type, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate(Type type, JsonSchemaResolver schemaResolver)
at NSwag.Generation.OpenApiSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](TSchemaType schema, ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate(ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.GenerateInheritance(ContextualType type, JsonSchema schema, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NSwag.Generation.OpenApiSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](TSchemaType schema, ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](Type type, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate(Type type, JsonSchemaResolver schemaResolver)
at NSwag.Generation.OpenApiSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](TSchemaType schema, ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](ContextualType contextualType, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.JsonSchemaGenerator.GenerateWithReferenceAndNullability[TSchemaType](ContextualType contextualType, Boolean isNullable, JsonSchemaResolver schemaResolver, Action2 transformation) at NSwag.Generation.OpenApiSchemaGenerator.GenerateWithReferenceAndNullability[TSchemaType](ContextualType contextualType, Boolean isNullable, JsonSchemaResolver schemaResolver, Action2 transformation)
at NJsonSchema.Generation.JsonSchemaGenerator.AddProperty(JsonSchema parentSchema, ContextualAccessorInfo property, JsonTypeDescription propertyTypeDescription, String propertyName, Attribute requiredAttribute, Boolean hasRequiredAttribute, Boolean isNullable, Object defaultValue, JsonSchemaResolver schemaResolver)
at NJsonSchema.NewtonsoftJson.Generation.NewtonsoftJsonReflectionService.LoadPropertyOrField(JsonProperty jsonProperty, ContextualAccessorInfo accessorInfo, Type parentType, JsonSchema parentSchema, NewtonsoftJsonSchemaGeneratorSettings settings, JsonSchemaGenerator schemaGenerator, JsonSchemaResolver schemaResolver)
at NJsonSchema.NewtonsoftJson.Generation.NewtonsoftJsonReflectionService.GenerateProperties(JsonSchema schema, ContextualType contextualType, NewtonsoftJsonSchemaGeneratorSettings settings, JsonSchemaGenerator schemaGenerator, JsonSchemaResolver schemaResolver)
at NJsonSchema.Generation.ReflectionServiceBase1.NJsonSchema.Generation.IReflectionService.GenerateProperties(JsonSchema schema, ContextualType contextualType, JsonSchemaGeneratorSettings settings, JsonSchemaGenerator schemaGenerator, JsonSchemaResolver schemaResolver) at NJsonSchema.Generation.JsonSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver) at NSwag.Generation.OpenApiSchemaGenerator.GenerateObject(JsonSchema schema, JsonTypeDescription typeDescription, JsonSchemaResolver schemaResolver) at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](TSchemaType schema, ContextualType contextualType, JsonSchemaResolver schemaResolver) at NJsonSchema.Generation.JsonSchemaGenerator.Generate[TSchemaType](ContextualType contextualType, JsonSchemaResolver schemaResolver) at NJsonSchema.Generation.JsonSchemaGenerator.GenerateWithReferenceAndNullability[TSchemaType](ContextualType contextualType, Boolean isNullable, JsonSchemaResolver schemaResolver, Action2 transformation)
at NSwag.Generation.OpenApiSchemaGenerator.GenerateWithReferenceAndNullability[TSchemaType](ContextualType contextualType, Boolean isNullable, JsonSchemaResolver schemaResolver, Action2 transformation) at NSwag.Generation.AspNetCore.Processors.OperationResponseProcessor.Process(OperationProcessorContext operationProcessorContext) at NSwag.Generation.AspNetCore.AspNetCoreOpenApiDocumentGenerator.RunOperationProcessors(OpenApiDocument document, ApiDescription apiDescription, Type controllerType, MethodInfo methodInfo, OpenApiOperationDescription operationDescription, List1 allOperations, OpenApiDocumentGenerator generator, OpenApiSchemaResolver schemaResolver)
at NSwag.Generation.AspNetCore.AspNetCoreOpenApiDocumentGenerator.AddOperationDescriptionsToDocument(OpenApiDocument document, Type controllerType, List1 operations, OpenApiDocumentGenerator swaggerGenerator, OpenApiSchemaResolver schemaResolver) at NSwag.Generation.AspNetCore.AspNetCoreOpenApiDocumentGenerator.GenerateApiGroups(OpenApiDocumentGenerator generator, OpenApiDocument document, IGrouping2[] apiGroups, OpenApiSchemaResolver schemaResolver)
at NSwag.Generation.AspNetCore.AspNetCoreOpenApiDocumentGenerator.GenerateAsync(ApiDescriptionGroupCollection apiDescriptionGroups)
at NSwag.Commands.Generation.AspNetCore.AspNetCoreToOpenApiCommand.GenerateDocumentWithDocumentProviderAsync(IServiceProvider serviceProvider) in C:\NSwag\NSwag-master\NSwag-master\src\NSwag.Commands\Commands\Generation\AspNetCore\AspNetCoreToOpenApiCommand.cs:line 245
at NSwag.Commands.Generation.AspNetCore.AspNetCoreToOpenApiCommand.GenerateDocumentAsync(IServiceProvider serviceProvider, String currentWorkingDirectory) in C:\NSwag\NSwag-master\NSwag-master\src\NSwag.Commands\Commands\Generation\AspNetCore\AspNetCoreToOpenApiCommand.cs:line 239
at NSwag.Commands.Generation.AspNetCore.AspNetCoreToOpenApiGeneratorCommandEntryPoint.Process(String commandContent, String outputFile, String applicationName) in C:\NSwag\NSwag-master\NSwag-master\src\NSwag.Commands\Commands\Generation\AspNetCore\AspNetCoreToOpenApiGeneratorCommandEntryPoint.cs:line 29
at System.RuntimeMethodHandle.InvokeMethod(Object target, Void** arguments, Signature sig, Boolean isConstructor)
at System.Reflection.MethodBaseInvoker.InvokeDirectByRefWithFewArgs(Object obj, Span1 copyOfArgs, BindingFlags invokeAttr) --- End of inner exception stack trace --- at System.Reflection.MethodBaseInvoker.InvokeDirectByRefWithFewArgs(Object obj, Span1 copyOfArgs, BindingFlags invokeAttr)
at System.Reflection.MethodBaseInvoker.InvokeWithFewArgs(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
at System.Reflection.MethodBase.Invoke(Object obj, Object[] parameters)
at NSwag.AspNetCore.Launcher.Program.Main(String[] args) in C:\NSwag\NSwag-master\NSwag-master\src\NSwag.AspNetCore.Launcher\Program.cs:line 132

[rpskelton2]

This error is from RicoSuter/Namotion.Reflection#143
There's even a draft PR for the fix RicoSuter/Namotion.Reflection#151

@RicoSuter - any chance we can get a new version of nswag that includes this fix?

[TheXenocide]

Just wanted to check in here, it looks like the pull request that solves this issue has been accepted, just wondering if we know when we'll be able to take a fix? We're working around it for now with locally built packages, but we would love to remove those before our current work goes to production.

[Smoovsky]

Just wanted to check in here, it looks like the pull request that solves this issue has been accepted, just wondering if we know when we'll be able to take a fix? We're working around it for now with locally built packages, but we would love to remove those before our current work goes to production.

Currently, we build Namotion.Reflection from the latest source code and then reference the DLL directly as the walkaround. I hope a version upgrade addressing this issue will be released soon.